Thanks Christian for those informations!
Is this comparing of your chanter or uillean pipes chanters at all to well-tempered tuning?
I have to ask but I know it will be offtopic. All whistles and irish flutes are tuned this way?
The difference in cents between the exact tuning of 12-semitones in the tempered tuning to the real harmonies in the pure tuning is theory and comes from physical calculations as well as from the common sense of human musicallity. Pipes have to be tuned so and mine are as all others that I have heard. If they would not be tuned so they would sound terribly wrong.
In reality if you measure the Pipes they vary in tone +/- 3…5 Cents around the theoretic pure tuning by the pressure of the air. Flutes, saxophones and other mouth blown instruments do as well as the human voice will vary. If you test a Chanter, a Whistle or a Concert Flute you’ll recognise the range of variability also around their theroretic tuning, pure or tempered scale depends on their kind of construction.
The Pipes have to be tuned to that pure schematic because of their upper partial harmonics. Flutes and Whistles do not have such a range of upper harmonics so that the effect does not appear so obviously. Most of the Whistles are additionally not eactly tuned except some expensive ones as e.i. Abell Whistles.
Some examples of pure tuning and the theory are to be found here: http://en.wikipedia.org/wiki/Musical_tuning, http://de.wikipedia.org/wiki/Reine_Stimmung
I spotted this CD in a charity shop today:
http://www.linnrecords.com/recording-les-douze-noëls-hdcd.aspx
Didn’t buy it. Really couldn’t imagine uilleann pipes sounding any good in that repertoire. French 18th century pipes, yes.